<template>
  <div class="app-container">
    <h2 style="text-align: center">发布新课程</h2>
    <el-steps
      :active="1"
      process-status="wait"
      align-center
      style="margin-bottom: 40px"
    >
      <el-step title="填写课程基本信息" />
      <el-step title="创建课程大纲" />
      <el-step title="提交审核" />
    </el-steps>
    <el-form label-width="120px">
      <el-form-item label="课程标题">
        <el-input
          v-model="courseInfo.title"
          placeholder=" 示例：机器学习项目课：从基础到搭建项目视频课程。专业名称注意大小写"
        />
      </el-form-item>

      <!-- 所属分类  -->
      <!-- 一级分类 -->

      <el-form-item label="课程分类">
            <el-select
                v-model="courseInfo.subjectParentId"
                placeholder="一级分类" @change="subjectLevelOneChanged">

                <el-option
                    v-for="subject in subjectOneList"
                    :key="subject.id"
                    :label="subject.title"
                    :value="subject.id"/>

            </el-select>

            <!-- 二级分类 -->
            <el-select v-model="courseInfo.subjectId" placeholder="二级分类">
                <el-option
                    v-for="subject in subjectTwoList"
                    :key="subject.id"
                    :label="subject.title"
                    :value="subject.id"/>
            </el-select>
        </el-form-item>
      <!-- 课程讲师  -->
      <el-form-item label="课程讲师">
        <el-select
            v-model="courseInfo.teacherId"
            placeholder="请选择">

            <el-option
                v-for="teacher in teacherList"
                :key="teacher.id"
                :label="teacher.name"
                :value="teacher.id"/>

        </el-select>
        </el-form-item>

      <el-form-item label="总课时">
        <el-input-number
          :min="0"
          v-model="courseInfo.lessonNum"
          controls-position="right"
          placeholder="请填写课程的总课时数"
        />
      </el-form-item>


      <!-- 课程简介-->

      <el-form-item label="课程简介">
        <tinymce :height="300" v-model="courseInfo.description" />
      </el-form-item>

      <!-- 课程封面 -->
       <el-form-item label="课程封面">

            <el-upload
                :show-file-list="false"
                :on-success="handleAvatarSuccess"
                :before-upload="beforeAvatarUpload"
                :action="BASE_API+'/eduoss/fileoss'"
                class="avatar-uploader">
                <img :src="courseInfo.cover" style="width:500px">
            </el-upload>

        </el-form-item>

      <el-form-item label="课程价格">
        <el-input-number
          :min="0"
          v-model="courseInfo.price"
          controls-position="right"
          placeholder="免费课程请设置为0元"
        />
        元
      </el-form-item>

      <el-form-item>
        <el-button
          :disabled="saveBtnDisabled"
          type="primary"
          @click="saveOrUpdate"
          >保存并下一步</el-button
        >
      </el-form-item>
    </el-form>
  </div>
</template>

<script>
import Tinymce from "../../../components/Tinymce";
import course from "../../../api/edu/course";
import subject from "../../../api/edu/subject";
import teacher from "../../../api/edu/teacher";
export default {
  components:{Tinymce},
  data() {
    return {
      saveBtnDisabled: false, // 保存按钮是否禁用
      courseInfo: {
        title: "",
        subjectId: "",//二级分类
        subjectParentId: '',//一级分类
        teacherId: "",
        lessonNum: 0,
        decription: "",
        cover: "/static/001.jpg",
        price: 0,
      },
      courseId:'', // 课程id
      BASE_API: process.env.BASE_API,
      // 一级分类列表
      subjectOneList:[],
      // 二级分类列表
      subjectTwoList:[],
      // 讲师列表
      teacherList:[],
    };
  },
  created() {
    // 获取路由中的课程id
    if(this.$route.params && this.$route.params.id) {
      this.courseId = this.$route.params.id
      this.getCourse()
    }else{
      // 初始化一级分类
      this.getAllSubject()
      //初始化老师猎列表
      this.findAll()
    }
  },
  methods: {
    //获取课程信息
    getCourse() {
      course.getCourse(this.courseId).then(response =>{
        this.courseInfo = response.data.courseInfoVo
        
        // 查询所有分类
        subject.getAllSubject().then(response=>{
          // 一级分类
          this.subjectOneList = response.data.list
          // 二级分类
          for(var i=0;i<this.subjectOneList.length;i++){
            var oneSubject = this.subjectOneList[i]
            if(this.courseInfo.subjectParentId === oneSubject.id) {
              this.subjectTwoList = oneSubject.children
            }
          }
         this.findAll()
        
         })
      })
    },
    // 上传封面成功的调用方法
    handleAvatarSuccess(response){
        this.courseInfo.cover = response.data.url
    },
    //上传之前调用的方法
    beforeAvatarUpload(file){
      const isJPG = file.type === 'image/jpeg'
      const isLt2M = (file.size / 1024 / 1024) < 2
       if (!isJPG) {
                this.$message.error('上传头像图片只能是 JPG 格式!')
            }
       if (!isLt2M) {
                this.$message.error('上传头像图片大小不能超过 2MB!')
            }
       return isJPG && isLt2M
    },
    // 获取讲师列表
    findAll(){
      teacher.findAll().then(response=>{
          this.teacherList = response.data.items
      })
    },
    // 点击一级分类显示对应二级分类
    subjectLevelOneChanged(value){
        for(var i=0;i<this.subjectOneList.length ;i++){
          var oneSubject = this.subjectOneList[i]
          //选中的id和数组中的id对应
          if(value == oneSubject.id){
            this.subjectTwoList = oneSubject.children
            this.courseInfo.subjectId = ''
          }
        }
    },

    // 查询所有一级分类
    getAllSubject() {
      subject.getAllSubject().then(response=>{
          this.subjectOneList = response.data.list
      })
    },
    //
    saveOrUpdate() {
      if(!this.courseInfo.id){
        this.saveCourse()
      }else{
        this.updateCourse()
      }
    },
    // 修改课程
    updateCourse() {
      course.updateCourse(this.courseInfo).then(response =>{

        this.$message({
          type: "success",
          message: "修改成功"
        });
        this.$router.push({path:'/edu/course/chapter/'+this.courseId})
      }).catch((response) => {
        this.$message({
          type: "error",
          message: "修改失败",
        });
      });
    },
    // 添加课程
    saveCourse() {
      course
        .saveCourse(this.courseInfo)
        .then((response) => {
          this.$message({
            type: "success",
            message: "保存成功!",
          });
          this.$router.push({
            path: "/edu/course/chapter/" + response.data.courseId,
          });
        })
        .catch((response) => {
          this.$message({
            type: "error",
            message: response.message,
          });
        });
    },

  },
};
</script>
<style scoped>
.tinymce-container {
  line-height: 29px;
}

</style>
